This 5.1 MHz circuit was found in a 1980s documentation. The frequency is given by the crystal and general purpose transistors can be used.
This circuit was found in an Electronics Now from the 90's. The integrated regulator circuit and...
This circuit is suggested by National Semiconductor in its Linear Applications Handbook. It makes...
The circuit shown is from the 1993 Motorola Linear Interface ICs. The power source may be common...